Tool for grinding valves



April 30, 1935. o. BEARD TOOL FOR GRINDING VALVES Filed Jan. 18, 1955 Patented Apr. 30, 1935 UNITED STATES Claims.

My invention relates toa tool for grinding valves and more particularly the conical valves in the motor blocks of internal combustion engines.

The principal object of my invention is to provide a grinding tool for conical valves which will present aplurality of spaced relatively narrow grinding surfaces, thus speeding up the grinding action.

Another object is to provide a tool having an abrasive element removably mounted therein which is adapted to be shifted when worn to present new grinding surfaces. v

A further object is to provide a tool whereby a uniform grinding or cutting action is assured with a minimum application of force.

These and other objects will be apparent when the specification is considered with the accompanying drawing, in which:

Figure 1 is a side view of the tool;

Figure 2 is a plan view of the assembled tool;

Figure 3 is an enlarged cross sectional elevation of the assembled tool;

Figure 4 is a plan view of the abrasive disk; and

Figure 5 is a section through a portion of the conical grinding shell.

Referring more particularly to the drawing, the numeral I designates the tool generally comprising a substantially conical shell 2, preferably formed of a die casting or the like. The shell has a truncated, conical body portion 3 that tapers to a hollow extensin i at one end, which extension has a bore 5 extending therethrough for the reception of a stem 6 of a poppet valve 1.

The conical body portion 3 of the shell 2 is provided with a plurality of substantially U-shaped, outwardly flaring radial folds 9, preferably five in number, extending from the upper edge or lip Ill of the shell to the end of the conical body portion at a slightly decreased pitch from that of the body portion. These folds form and are interposed between a plurality of spaced fiat working areas or faces 8. These working faces, which merge with the side walls ll of the U-shaped folds 9, are ground down to provide flat narrow V-shaped Valve engaging portions 12 at the inner or lower ends of the working faces 8, and to provide a flat supporting surface l3, at

each side thereof for a purpose presently de- I4 is seated within the shell 2 and caused to conform closely to the contour of the latter by means of a substantially rigid or semi-rigid clamping member or spider 56 formed of slightly yielding metal. Clamping member l6 comprises a narrow annular 'or ring-like portion H, the bore and diameter of which are respectively just sufficient to permit of the clamping member being sleeved over a slotted bushing or sleeve 18 which is positioned inand extends through the bore 5 of the extension i. The bushing i8 is provided with a collar l9 onthe upper-end thereof which is adapted to engage the ring-likeportion ii. and retain the clamping memberifi in position. The lower end of the bushing is externally threaded as at 26, to receive thereon the clamp nut 2| for tightly clamping the collar is of the bushing i8 against the ring-like portion I! of the clamping member. An adapter or bushing 22, adapted to be snugly sleeved within the bushing I8, is provided with an enlarged knurled lower end portion 23 which contacts the lower end of the threaded bushing 58 when the parts are assembled. The stem 6 of the valve is adapted to be snugly received in the bore of the bushing 22.

Projecting upwardly and outwardly from the annulus ll of clamping member It, are a plurality of arms 24, one for each fold 9, in which fold these arms are adapted to snugly fit when the, latter, together with the adjacent portions of the abrasive disk, are pressed thereinto. The arms are ll-shaped and tapered to snugly fit and conform with the folds 9, and serve to clamp or press the abrasive cloth against the sides of the folds. The flat supporting surfaces l3 on the flat inner working faces 8 of the shell serve as a backing for the folded portions of the abrasive disk and obviate the necessity of sharply bendingor folding the disk at a right angle and therebycracking or otherwise weakening the disk at this point.

The extension 5 is formed with flat side faces 25, to provide a gripping surface for a vise or the like, not shown, for retaining the shell in nonrotatable position during the grinding operation. According to common practice, the valve I is provided with holes, or the like, 26, in the upper face thereof whereby the valve may be rotated by means of a suitable tool, not shown.

To assemble my device I seat the abrasive disk i i and clamping spider it within the shell 2. The bushing l 8 is then positioned Within the bore 5 of the shell, thereby clamping the arms 24 of the spider l6 and disk M within the U-shaped folds 9. Clamp nut 2i, threaded on the end of faces may be readily presented by rotating the disk a suitable distance.

Having thus described my invention:

What I claim is: V 7

1. A tool for grinding valves comprising aconical grinding shell adapted to receive a valve therein, said grinding shell having substantially U-shaped folds therein, an abrasive disk adapted to cover the inside of said grinding shell. and fit in said folds, a clamping element for clampingsaid abrasive diskin said grinding shell having arms adapted to-fit into said folds for holding said abrasive disk in saidshell.

2'.- A tool for grinding valves comprisingia conical grinding shell adapted to receive a valve havingta stem therein, a bore in said conical grinding shell. for receiving the valve stem therethrough, said grinding shell having outwardly extending substantially U-shape'd' folds therein, an abrasive diskremovably mounted in said shell, a semir-igidmetal clamping element having V-shaped tapered-armsfor clamping said disk in said folds, and a member in said bore'for retaining said clamping element in: position within the folds.

3. A-tool for grinding valves comprising a con ical grinding shell adaptedto receive a valve and valve stem'therein, a bore in said shell for receiving thevalve stem therethrough, said shell having substantially U-shaped outwardly extending folds therein, an abrasive disk removably mounted in said shell, a semi-rigid metal clamping member having v-shaped tapered arms adapted to fit in said folds for clamping the disk against said shell, and an adapter in said bore for retaining said clamping member in position within said shell.

4. A tool for grinding valves comprising a conical grinding shell adapted to receive a valve and Valve stem therein, said shell having flat working surfaces thereon, said working surfaces having relatively small V-shaped grinding faces thereon, said shell having substantially U-shaped folds therein, an abrasive disk removably mounted in said shell, aisemi-rigid clamping member having V-shaped tapered arms adapted to fit in said folds for clamping the disk against said shell.

5. Atool for grinding valves comprising a conicalgrinding shell adapted to receive avalve and valve: stem therein, saidshell having substantially U-shaped folds therein, a plurality of flat workfaces in said shell, saidworking faces-being ground. down to form V-shaped' valve engaging portions on said working faces, an abrasive disk removably mounted in said shell, said ground down portions adapted to provide aflat backing for the folded portions of said disk for preventing said disk from cracking at the.- folds, a semirigid clamping member having V-shaped tapered arms adapted to fit insaidfolds for clamping the disk against said shell.

LAWRENCE Q. BEARD. 

